Complex electrically operated ground and test device using vacuum circuit interrupters and methods of operating the same

Abstract

A grounding and test device includes a chassis configured to be removably installed in a drawout switchgear compartment (e.g., a breaker compartment) having a load conductor and a line conductor therein. The device also includes an interconnection bus supported by the chassis and a ground conductor supported by the chassis. The device further includes a first vacuum circuit interrupter supported by the chassis and configured to selectively couple and decouple the interconnection bus and the line conductor, a second vacuum circuit interrupter supported by the chassis and configured to selectively couple and decouple the interconnection bus and the load conductor and a third vacuum circuit interrupter supported by the chassis and configured to selectively couple and decouple the interconnection bus and the ground conductor.

That which is claimed: 
     
       1. A grounding and test device comprising:
 a chassis configured to be removably installed in a drawout switchgear compartment having a load conductor and a line conductor therein; 
 an interconnection bus supported by the chassis; 
 a ground conductor supported by the chassis; 
 a first vacuum circuit interrupter supported by the chassis and configured to selectively couple and decouple the interconnection bus and the line conductor; 
 a second vacuum circuit interrupter supported by the chassis and configured to selectively couple and decouple the interconnection bus and the load conductor; and 
 a third vacuum circuit interrupter supported by the chassis and configured to selectively couple and decouple the interconnection bus and the ground conductor. 
 
     
     
       2. The grounding and test device of  claim 1 :
 wherein the first vacuum circuit interrupter comprises a plurality of first vacuum circuit interrupters, respective ones of which are configured to selectively couple and decouple the interconnection bus and respective ones of a plurality of line conductors; and 
 wherein the second vacuum circuit interrupter comprises a plurality of second vacuum circuit interrupters, respective ones of which are configured to selectively couple and decouple the interconnection bus and respective ones of a plurality of load conductors. 
 
     
     
       3. The grounding and test device of  claim 1 :
 wherein the chassis comprises a housing having a vertical rear face configured to face into the switchgear compartment when the chassis is installed; 
 wherein first vacuum circuit interrupter is included in a first elongate pole unit mounted on and extending from the vertical rear face of the housing; and 
 wherein the second vacuum circuit interrupter is included in a second elongate pole unit mounted on and extending from the vertical rear face of the housing. 
 
     
     
       4. The grounding and test device of  claim 3 :
 wherein a first end of the first pole unit is mounted at the vertical rear face of the housing and wherein the first pole unit comprises a contact disposed at a second end of the first pole unit and configured to engage the line conductor when the chassis is installed in the breaker compartment; and 
 wherein a first end of the second pole unit is mounted at the vertical rear face of the housing and wherein the second pole unit comprises a contact disposed at a second end of the second pole unit and configured to engage the load conductor when the chassis is installed in the breaker compartment. 
 
     
     
       5. The grounding and test device of  claim 3 , wherein the interconnection bus comprises an elongate bus bar extending horizontally between the first and second pole units and mounted on the vertical rear face of the housing. 
     
     
       6. The grounding and test device of  claim 5 , further comprising at least one insulating standoff mounted on the vertical rear face of the housing and supporting the bus bar. 
     
     
       7. The grounding and test device of  claim 5 , wherein the third vacuum circuit interrupter is included in a third elongate pole unit mounted on the chassis beneath the first and second pole units and the bus bar and extending longitudinally in a direction orthogonal to longitudinal axes of the first and second pole units. 
     
     
       8. The grounding and test device of  claim 7 , wherein the bus bar comprises a first bus bar and further comprising a second elongate bus bar connected to the first bus bar and extending perpendicularly therefrom to contact a terminal of the third pole unit. 
     
     
       9. The grounding and test device of  claim 4 , further comprising a controller supported by the chassis and configured to control the first and second pole units. 
     
     
       10. The grounding and test device of  claim 9 , further comprising:
 a first control switch coupled to the controller and configured to control the first vacuum circuit interrupter pole unit; and 
 a second control switch coupled to the controller and configured to control the second vacuum circuit interrupter pole unit. 
 
     
     
       11. The grounding and test device of  claim 10 , wherein the controller and the first and second switches are mounted in a panel removably attached at the front face of the housing. 
     
     
       12. The grounding and test device of  claim 1 , wherein the drawout switchgear compartment comprises a breaker compartment. 
     
     
       13. A grounding and test device comprising:
 a chassis configured to be removably installed in a drawout switchgear compartment having a plurality of load conductors and a plurality of line conductors therein, the chassis comprising a housing having a vertical front face configured to face outward from the circuit breaker housing when the chassis is installed therein and a vertical rear face on an opposite side of the housing from the first vertical face and configured to face inside the switchgear compartment; 
 a horizontal row of spaced apart first vacuum circuit interrupter pole units mounted on the vertical rear face of the housing and extending perpendicularly therefrom, the first vacuum circuit interrupter pole units having respective contacts configured to engage respective ones of the plurality of line conductors; 
 a horizontal row of spaced apart second vacuum circuit interrupter pole units mounted on the vertical rear face of the housing and extending perpendicularly therefrom parallel to the row of first vacuum circuit interrupter pole units, the second vacuum circuit interrupter pole units having respective contacts configured to engage respective ones of the plurality of load conductors; 
 an elongate interconnection bus bar mounted on the vertical rear face of the housing, extending horizontally between the rows of first and second vacuum circuit interrupter pole units; 
 respective flexible conductors extending perpendicularly from the interconnection bus bar and connecting respective ones of the first and second vacuum circuit interrupter pole units to the interconnection bus bar; 
 a ground conductor supported by the chassis; and 
 a third vacuum circuit interrupter pole unit supported by the chassis and coupled between the interconnection bus and the ground conductor. 
 
     
     
       14. The grounding and test device of  claim 13 , wherein the third vacuum circuit interrupter pole unit is positioned below the rows of first and second vacuum circuit interrupter pole units and longitudinally extends along a direction orthogonal to longitudinal axes of the first and second vacuum circuit interrupter pole units. 
     
     
       15. The grounding and test unit of  claim 14 , further comprising a ground connection bus extending perpendicularly from the interconnection bus to contact the third vacuum circuit interrupter pole unit and passing between adjacent vacuum circuit interrupter pole units of a lower row of the rows of first and second vacuum circuit interrupter pole units. 
     
     
       16. The grounding and test unit of  claim 13 , further comprising a controller configured to control the first, second and third vacuum circuit interrupter pole units. 
     
     
       17. The grounding and test unit of  claim 16 , further comprising respective switches coupled to the controller and configured to control respective ones of the first, second and third vacuum circuit interrupter pole units. 
     
     
       18. A method comprising:
 installing a grounding and test device in a drawout switchgear compartment having a load conductor and a line conductor therein, the grounding and test device comprising a first vacuum circuit interrupter configured to coupled between an interconnection bus and the line conductor, a second vacuum circuit interrupter configured to be coupled between the interconnection bus and the load conductor, and a third vacuum circuit interrupter configured to be coupled between the interconnection bus and a ground conductor; 
 closing the first third vacuum circuit interrupter and the third vacuum circuit interrupter while maintaining the second vacuum circuit interrupter in an open state to ground the line conductor; and 
 closing the second vacuum circuit interrupter and the third vacuum circuit interrupter while maintaining the first vacuum circuit interrupter in an open state to ground the load conductor. 
 
     
     
       19. The method of  claim 18 , further comprising closing the first and second vacuum circuit interrupters while maintaining the third vacuum circuit interrupter in an open state. 
     
     
       20. The method of  claim 18 :
 wherein the first vacuum circuit interrupter is one of a plurality of first vacuum circuit interrupters, respective ones of which are configured to be coupled between the interconnection bus and respective line conductors of the switchgear compartment; 
 wherein the second vacuum circuit interrupter is one of a plurality of second circuit vacuum interrupters, respective ones of which are configured to be coupled between the interconnection bus and respective load conductors of the switchgear compartment; 
 wherein closing the first third vacuum circuit interrupter and the third vacuum circuit interrupter while maintaining the second vacuum circuit interrupter in an open state to ground the line conductor comprises closing the plurality of first vacuum circuit interrupters and the third vacuum circuit interrupter while maintaining the plurality of second vacuum circuit interrupters in an open state to ground the plurality of line conductors; and 
 wherein closing the second vacuum circuit interrupter and the third vacuum circuit interrupter while maintaining the first vacuum circuit interrupter in an open state to ground the load conductor comprises closing the plurality of second vacuum circuit interrupters and the third vacuum circuit interrupter while maintaining the plurality of first vacuum circuit interrupters in an open state to ground the plurality of load conductors.